Question

The fourth term of an A.P. is 11. The sum of the fifth and seventh terms of A.P. is 34.find common difference

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

Step-by-step explanation:

$a_{4} = 11 \\ a + 3d = 11\\ 3d= 11-a\\ d= (11-a)/3\\a_{5} + a_{7} = 34 \\ a+4d +a +6d = 34\\2a + 10d = 34\\2a + 10(\frac{11-a}{3} ) = 34 \\6a +110 - 10a = 102\\8= 4a\\2= a\\a + 3d = 11\\2 + 3d = 11\\3d = 9\\d = 3\\Voila!!$